Attachment plug



Feb. 9' 1926.

ATTACHMENT PLUG Filed Nov. 20. 1920..

Patented Feb. 9, 1926.

UNITED STATES PATENT OFFICE.v

STANLEY McCLATCI-IIE, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO BENJAMIN ELECTRIC MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION .0F ILLINOIS.

ATTACHMNT PLUG.

Application led November 2G, 1920. Serial No. 425,328.

T0 all w hom it may concern Be it known that I, STANLEY MoCLA'roi-irn, a citizen ot the United States.` residing at Cambridge. in the county ot Middlesex and State of Massachusetts, have invented new and useful Improvements in Attachment Plugs, ot' which the following is a tulh clear, concise, and exact description, reterence being had to the accompanying drawing. forming a part of this specilication.

M v invention relates to electrical connector devices and more particularly to attachment plugs.

One of the objects otl my invention is to cheapen the construction and lessen the danger ot breakage by doing awav with molded insulating parts.

A further object ot my invention is to provide an attachment plug which will be durable and eliicient in use, and simple and compact in construction.

Further objects will appear from the detailed description to follow and from the appended claims:

In the drawings, in which two embodiments of my invention are shown- Fig. 1 is a view of the inner or entering end ot a swivel lattachment plug;

Fig. 2 is a part sectional, part elevational `view ot the swivel plug shown in Fig. 1:

Fig. 3 is a section on the line 3 3 of Fig. Q;

Fig. 4f is a plan view ot an insulating filtre washer used in the plug construction;

Fig. 5 is a view of the inner or entering end ot' another form of plug embodying my invention Fig. 6 is a part sectional, part elevational view oi the swivel shell plug shown in Fig'. 5; and v Fig. 7 is a plan view of a sliding Contact member used in the construction ot Figs. and G.

Referring to Figs. 1, 2, 3 and 4. the construction shown therein comprises in a general way a swivel threaded shell contact 10. a conical sliding contact member 11, havingI its circular edge swivelly connected with the inner or entering end ot the threaded shell contact at 12, a binding screw 13 threaded into the swivel Contact member 11, a combined center contact and binding screw .141, a pair of insulating washers 15 and 16, by

means of which the center Contact screw 14 is mounted on the sliding contact 11 and insulated with respect thereto, and a sheet metal stamping 17 which serves two purposes, that ot clamping the insulating washers 15 and 16 in engagement with the sliding contact 11 and oit confining the strands ot the wire which lead to the center contact screw. i

Contact 10 into the socket. an insulating tibre band 1S) being provided between the thread ed shell contact 10 and the handle member. The three parts that is, the threaded shell, the insulating libre band 19 and they handle member 18, are secured together by a circular series ot corresponding depressions 20 formed in all three of the connecting members. By the above construction, it will be noted that the use ot molded insulation is entirely avoided, whereby a light, cheap, practically unbreakable construction is sccured. Y

Attention is called to thepeculiaritv of the tubular conductor confining portion 2l ot' the member 17, in that it is itself ot metal, and yet serves to prevent the conductor from coming in contact with the sliding contact 11, through which the conductor passes tothe center contact.

As shown in Figs.y 2 and 3, this tubular cord coniining portion 21 is Vspaced from the edge ot' the opening 211l in the sliding contact 11 through which opening 21a the tubular portion 21 extends. The member 17 has an eyelet portion 22 which extends through aligned openings in the insulating washers 15 and 16, this eyelet portion 22 being riveted over to firmly clamp the washers in engagement with the inwardly extending flange 4portion 23 of the sliding contact.

At-sheet metal handle member 18 is provided for screwing the threaded `shell passed through the tubular conductor conlining member 20, and clamped underneath the headkot' the screw 14, andthe other conductor ispassed through the openingQl and clamped under the head ot the binding screw .13,

In screwingtheplug 'into the socket, the threaded shell contact l() swivels onthe sliding contact member ll so that the cords are not twisted by screwing in the plug.

In order to prevent chatingot the cords by the handle member 18, this handle member is provided ovith'an'inwardly extending cord conlining portion 26, which terms a smooth extending surface for the conductors torbear against.

,The construction shown in Figs. 5, 6 and 7, is quitesimilar'to the construction just described, except-,that here'the sliding Contact member 26 is substantially flat instead ot' being conicall and thatthel sheet metal stamping 27 which contines the cord leading toA the center contactris ot somewhat diiterent construction, and in that the sheet metal handlemember 28 is elongated and reduced to enable the plug to be screwed into a socket which is diiiicult of access to the ordinary plug.

The stamping 27 is'provi'ded with a pair of eyelet portions 29 by means ot which it is -secured'to the sliding contactmember QG, suitable insulating wasl'iers 30 being provided through which 'the eyelet portion-s Q9 extend` t'or insulatingv the stamping Q'iirom the sliding contact 26. In order to keep the strands ofthe conductor which is connected tothe binding screw 13 away from thefcenter contact screw 14, the sliding contact 2G vis provided with a Vsemi-circular upwardly extending vflange 3l.'

The sheet metal handle 28 may be provided at its outer end with' affibre band 32,

forming athumbpiece, this fibre band Ibe- 111g slrppedf on over a reduced `portion 33' otthe lfrandl'e, -andheld mplace by Hanging over the sheet metal handle as indicated at 34.

lVhile I have shown buttwo embodiments ot my invention it may be embodied in other forms covered and defined by the appended claims. n y n It is obvious that the handle shown iirFig. '6 may be substituted in the construction shown in Fig. 2.

Having thus described my invention what pI claim as newand desire to. secure by Letters Patent of the United States is:

l. A swivel shell attachment-plug comprising a threadedshellwcontacha sheet metal cap member extencing across the inner end ot said threadedshell contact, and having a swively connection therewithv5 a binding;

plate meriber mounted onv said sheet metal cap and insulated therefrom, a landing screw threadedinto said'binding plate, said cap ,member .having an opening therethrough, and :an eyelet member extending through said opening ior the conductor leading to said binding screw, said eyelet and said binding` plate member being i'orm'edas parts of an integral sheet metal stamping.

2. `Aswivel shell attachment plug comprising a threaded shell contact, asheet metal cap member extending across the inner endA STA NLEY Mo @LATCH IIC. 

